133 résultats pour "physical"
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Stroke.
IV DIAGNOSIS The symptoms typical of a stroke can also be caused by other conditions, including brain tumors, various infections, and overdoses of certain drugs. A patient that hasstrokelike symptoms may undergo a battery of imaging techniques to rule out other medical problems and confirm that a stroke has occurred. The key imagingtechnique used in diagnosing strokes is computed tomography (also known as CT or CAT scanning), which employs X rays to obtain images of the internal structures oft...
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Suicide.
C Sociological Theories Most social scientists believe that a society’s structure and values can influence suicide rates. French sociologist Émile Durkheim argued that suicide rates are related tosocial integration —that is, the degree to which an individual feels part of a larger group. Durkheim found suicide was more likely when a person lacked social bonds or had relationships disrupted through a sudden change in status, such as unemployment. As one example of the significance of social bond...
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Condorcet, Marie-Jean-Antoine-Nicolas Caritat de
years he also came under the influence of Euler, Fontaine, the Bernouillis and, above all, of the distinguished mathematician and academician, Jean Le Rond D'Alembert , who became his patron. He was elected Perpetual Secretary of the Academy of Sciences in 1773, and in 1782 became a member of the French Academy. An enthusiastic supporter and theorist of the Revolution, he played an important role in the drafting of the Déclaration des droits in 1789. Suspected later of being a Girondin, he w...
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Discrimination.
Throughout United States history many other groups have suffered racial or religious discrimination. Since Europeans first came to America, Native Americans havebeen forcibly deprived of their lands and denied civil rights. Congress enacted the Indian Civil Rights Act in 1968, and the federal courts have entertained a number ofsuits designed to restore to Native American tribes ancestral lands and hunting and fishing rights. Many religious groups, including Roman Catholics, Jews, and others,have...
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Mental Illness.
note that under this definition, political dissidents could be considered mentally ill for refusing to accept the dictates of their government. VI PREVALENCE Mental illness affects people of all ages, races, cultures, and socioeconomic classes. The prevalence of mental illness refers to how many people experience a mentalillness during a specified time period. A United States and Worldwide In the United States, researchers estimate that about 24 percent of people 18 or older, or about 44 mill...
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Human Evolution.
Strepsirhines are the most primitive types of living primates. The last common ancestors of strepsirhines and other mammals—creatures similar to tree shrews andclassified as Plesiadapiformes—evolved at least 65 million years ago. The earliest primates evolved by about 55 million years ago, and fossil species similar to lemursevolved during the Eocene Epoch (about 55 million to 38 million years ago). Strepsirhines share all of the basic characteristics of primates, although their brains are notpa...
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Human Evolution - biology.
classified as Plesiadapiformes—evolved at least 65 million years ago. The earliest primates evolved by about 55 million years ago, and fossil species similar to lemursevolved during the Eocene Epoch (about 55 million to 38 million years ago). Strepsirhines share all of the basic characteristics of primates, although their brains are notparticularly large or complex and they have a more elaborate and sensitive olfactory system (sense of smell) than do other primates. B Haplorhines B1 Tarsiers T...
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Pablo Picasso.
Color juxtapositions—between blue and orange, for instance—are intentionally strident and unharmonious. The representation of space is fragmented and discontinuous. While the left side of the canvas is largely Iberian-influenced, the right side is inspired by African masks, especially in its striped patterns and oval forms. Suchborrowings, which led to great simplification, distortion, and visual incongruities, were considered extremely daring in 1907. The head of the figure at the bottom right,...
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Islam.
commanded to face the Kaaba, an ancient shrine in the city of Mecca. The Qur’an also refers to the recitation of parts of the Qur’an as a form of prayer. However, evenwith its numerous references, the Qur’an alone does not give exact instructions for this central ritual of prayer. The most detailed descriptions of the rituals for prayer derive from the example set by the prophet Muhammad and are preserved in later Islamic traditions. Somedetails of these rituals vary, however all Muslims agree t...
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Alcoholism.
Although a consensus is growing among health professionals that alcohol dependence is a disease, society’s attitudes toward individuals with drinking problems remainambivalent and confused. Until the mid-20th century, the typical picture of the alcoholic was of someone without steady employment, unable to sustain familyrelationships and most likely in desperate financial straits. But this stereotype was largely dispelled when highly respected people publicly admitted their alcoholdependence and...
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Atom
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INTRODUCTION
Water Molecule
A water molecule consists of an oxygen atom and two hydrogen atoms, which are attached at an angle of 105°.
spontaneously break apart and change, or decay, into other atoms. Unlike electrons, which are fundamental particles, protons and neutrons are made up of other, smaller particles called quarks. Physicists know of six different quarks.Neutrons and protons are made up of up quarks and down quarks —two of the six different kinds of quarks. The fanciful names of quarks have nothing to do with their properties; the names are simply labels to distinguish one quark from another. Quarks are unique amo...
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Physics
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INTRODUCTION
Physics, major science, dealing with the fundamental constituents of the universe, the forces they exert on one another, and the results produced by these forces.
Starting about 1665, at the age of 23, Newton enunciated the principles of mechanics, formulated the law of universal gravitation, separated white light into colors,proposed a theory for the propagation of light, and invented differential and integral calculus. Newton's contributions covered an enormous range of naturalphenomena: He was thus able to show that not only Kepler's laws of planetary motion but also Galileo's discoveries of falling bodies follow a combination of his ownsecond law of m...
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Confucian philosophy, Korean
neglected by more traditional Confucianism. Read with new eyes, an entirely new level of meaning was uncovered in the ancient texts: they discovered a Confucian foundation for the meditative cultivation of consciousness that had been a particular strength of the Buddhists, and to frame it and provide an account of sagehood equal to Buddhist talk of enlightenment, they found a complete metaphysical system, a Confucian version of the kind of thinking that had been elaborated mainly under Daoist au...
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Comparative Anatomy.
In comparing two species, anatomists have to be careful to differentiate between homologous structures, which are ones that have evolved from a shared ancestor, andanalogous structures, which have developed from different origins. Homologous structures are built on the same underlying plan. A human arm, a bat’s wing, and awhale’s flipper look quite different from the outside, but the bones inside reveal that these limbs all have the same basic structure. Analogous structures, by contrast,often l...
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Statistics
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INTRODUCTION
Statistics, branch of mathematics that deals with the collection, organization, and analysis of numerical data and with such problems as experiment design and decision
making.
frequency, column (d), is the ratio of the frequency of an interval to the total count; the relative frequency is multiplied by 100 to obtain the percent relative frequency.The cumulative frequency, column (e), represents the number of students receiving grades equal to or less than the range in each succeeding interval; thus, thenumber of students with grades of 30 or less is obtained by adding the frequencies in column (c) for the first three intervals, which total 53. The cumulative relativef...
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Statistics
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INTRODUCTION
Statistics, branch of mathematics that deals with the collection, organization, and analysis of numerical data and with such problems as experiment design and decision
making.
Professional pollsters typically conduct their surveys among sample populations of 1,000 people. Statistical measurementsshow that reductions in the margin of error flatten out considerably after the sample size reaches 1,000.© Microsoft Corporation. All Rights Reserved. The raw materials of statistics are sets of numbers obtained from enumerations or measurements. In collecting statistical data, adequate precautions must be taken tosecure complete and accurate information. The first problem of...
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Meteorology.
to find the corresponding relative humidity and dew-point temperature. III SPECIAL METEOROLOGICAL INSTRUMENTS Meteorologists have developed several sophisticated instruments that measure multiple physical characteristics of the air simultaneously and at more than one location.The most important of these special instruments are radiosondes, Doppler radar, and weather satellites. A Radiosonde A radiosonde measures air temperature, air pressure, and humidity from the earth’s surface up to an alt...
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Genetics - biology.
construct identical buildings. Just as each contractor would require a full copy of the blueprint to construct a complete building, each new cell needs a complete copy ofan organism’s genetic information to function properly. Organisms use two types of cell division to ensure that DNA is passed down from cell to cell during reproduction. Simple one-celled organisms and other organisms thatreproduce asexually—that is, without the joining of cells from two different organisms—reproduce by a proces...
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Obesity.
of a day, contributing to the development of obesity. V TREATMENTS FOR OBESITY Obesity can become a chronic lifelong condition caused by overeating, physical inactivity, and even genetic makeup. No matter what the cause, however, obesity can beprevented or managed with a combination of diet, exercise, behavior modification, and in severe cases, weight-loss medications and surgery. A Diets The most common and conservative treatment for obesity utilizes a nutritionally balanced, low calorie diet...
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Dog.
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INTRODUCTION
Dog, mammal generally considered to be the first domesticated animal.
French word for butterfly because it has ears that resemble butterfly wings, is a happy, friendly dog, suitable for small living spaces. The final dog group, nonsporting ,includes a wide variety of purebreds that differ in size, coat, overall appearance, and personality, from the shorthaired spotted dalmatian to the curly-haired poodle. V DOG BEHAVIOR Instinctive behaviors of the domestic dog are comparable to those of its wild relatives, the wolf, coyote, fox, and jackal. Unlike trained behavi...
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Dog - biology.
French word for butterfly because it has ears that resemble butterfly wings, is a happy, friendly dog, suitable for small living spaces. The final dog group, nonsporting ,includes a wide variety of purebreds that differ in size, coat, overall appearance, and personality, from the shorthaired spotted dalmatian to the curly-haired poodle. V DOG BEHAVIOR Instinctive behaviors of the domestic dog are comparable to those of its wild relatives, the wolf, coyote, fox, and jackal. Unlike trained behavi...
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Albert Einstein
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INTRODUCTION
Albert Einstein (1879-1955), German-born American physicist and Nobel laureate, best known as the creator of the special and general theories of relativity and for his
bold hypothesis concerning the particle nature of light.
On the basis of the general theory of relativity, Einstein accounted for the previously unexplained variations in the orbital motion of the planets and predicted thebending of starlight in the vicinity of a massive body such as the sun. The confirmation of this latter phenomenon during an eclipse of the sun in 1919 became a mediaevent, and Einstein’s fame spread worldwide. For the rest of his life Einstein devoted considerable time to generalizing his theory even more. His last effort, the unifi...
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Albert Einstein.
On the basis of the general theory of relativity, Einstein accounted for the previously unexplained variations in the orbital motion of the planets and predicted thebending of starlight in the vicinity of a massive body such as the sun. The confirmation of this latter phenomenon during an eclipse of the sun in 1919 became a mediaevent, and Einstein’s fame spread worldwide. For the rest of his life Einstein devoted considerable time to generalizing his theory even more. His last effort, the unifi...
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Acting
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INTRODUCTION
Lee Strasberg
American acting teacher Lee Strasberg was best known for his association with the Actors Studio, of which he became the
artistic director in 1951.
truthfully felt those emotions at the moment they expressed them. Finding the true feeling in the proper place and time on stage, however, was a problem that Aristotleaddressed less well. He concluded that acting was an occupation for the gifted or insane. How to cross the artistic boundary beyond feigned emotions and flat imitation obsessed many Greek actors. In 315 BC the tragedian Polus carried the real ashes of his recently deceased son in an urn to stimulate a sense of genuine grief when h...
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Social Psychology.
During the 1960s, American psychologist Stanley Milgram studied a form of social influence stronger than conformity: obedience to authority. In a famous series ofexperiments that attracted controversy about human research ethics, Milgram put each of 1,000 subjects into a situation in which they were ordered by anexperimenter to administer painful electric shocks to a confederate (who did not actually receive any shocks). The subjects in these studies were led to believe that theywere acting as '...
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Quantum Theory
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INTRODUCTION
Quantum Theory, in physics, description of the particles that make up matter and how they interact with each other and with energy.
electron in the same way a particle with momentum would: It bumps the electron and changes the electron’s path. The light is also affected by the collision as though itwere a particle, in that its energy and momentum changes. Momentum is a quantity that can be defined for all particles. For light particles, or photons, momentum depends on the frequency, or color, of the photon, which in turndepends on the photon’s energy. The energy of a photon is equal to a constant number, called Planck’s cons...
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Extreme Sports.
racing events are the Raid Gauloises and the Eco-Challenge. Created in 1989 by French journalist Gerard Fusil, the Raid Gauloises is a grueling two-week adventure racein which five-person teams cross rugged and remote terrain. The inaugural Raid was held in New Zealand, and subsequent races have been staged in Costa Rica,Madagascar, Borneo, and Chile. The race has five separate stages designed to fit each location’s unique terrain. Stages may require horseback riding, white-waterpaddling, mounta...
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Domestic Violence.
socialization teaches boys and girls a belief system that devalues women—especially unmarried women—and creates a sense of female responsibility for themaintenance of the family. Women who believe that the end of a relationship or of a marriage represents a personal failure are less likely to leave abusive relationships. V TREATMENT AND PREVENTION A variety of programs and services, both for victims and offenders, exist to treat and prevent domestic violence. Since 1964, more than 1800 shelters...
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Heat (physics)
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INTRODUCTION
Heat Loss from a House
A thermograph shows the large amount of heat lost through a house's windows during winter.
Theoretically, the molecules of a substance would exhibit no activity at the temperature termed absolute zero. See Molecule. III TEMPERATURE SCALES Five different temperature scales are in use today: the Celsius scale, known also as the Centigrade scale, the Fahrenheit scale, the Kelvin scale, the Rankine scale, andthe international thermodynamic temperature scale ( see Thermometer). The Celsius scale, with a freezing point of 0° C and a boiling point of 100° C, is widely used throughout the...
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Animal Courtship and Mating - biology.
activity. These animals frequently copulate in water, and the penis helps transfer sperm before it is carried away by the currents Ostriches and rheas also contain apenis within the cloaca. Virtually all snakes and lizards display yet another variation of internal fertilization. Located in the tail are two penises, called hemepenes, which are covered by spinesand knobs that help lock it into place during mating. The male uses one hemepene at a time for copulation. Male salamanders secrete large...
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Depression (psychology).
IV CAUSES Some depressions seem to come out of the blue, even when things are going well. Others seem to have an obvious cause: a marital conflict, financial difficulty, or somepersonal failure. Yet many people with these problems do not become deeply depressed. Most psychologists believe depression results from an interaction betweenstressful life events and a person’s biological and psychological vulnerabilities. A Biological Factors Depression runs in families. By studying twins, researche...
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Sigmund Freud.
reminiscences from the past and about her daydreams. Remarkably, as her narrative revisited memories from the past, which were associated with the onset of aparticular symptom, each symptom disappeared when accompanied by an emotional outburst. Breuer made use of this discovery to eliminate her symptoms one at atime. He called the treatment the cathartic technique (from the Greek katharsis meaning “purgation”). The treatment was time consuming and required considerable effort to reach dimly re...
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Michelangelo
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INTRODUCTION
Michelangelo (1475-1564), Italian painter, sculptor, architect, and poet whose artistic accomplishments exerted a tremendous influence on his contemporaries and on
subsequent European art.
(17 ft) tall, was carved from a block of stone that another sculptor had left unfinished. Michelangelo drew on the classical tradition in depicting David as a nude,standing with his weight on one leg, the other leg at rest ( see contrapposto). This pose suggests impending movement, and the entire sculpture shows tense waiting, as David sizes up his enemy and considers his course of action. While David reveals Michelangelo's expert knowledge of anatomy (he had been dissecting corpses for about...
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Michelangelo.
(17 ft) tall, was carved from a block of stone that another sculptor had left unfinished. Michelangelo drew on the classical tradition in depicting David as a nude,standing with his weight on one leg, the other leg at rest ( see contrapposto). This pose suggests impending movement, and the entire sculpture shows tense waiting, as David sizes up his enemy and considers his course of action. While David reveals Michelangelo's expert knowledge of anatomy (he had been dissecting corpses for about...
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Nanotechnology.
ever-finer method of reducing material to the nanoscale size. Instead, nanostructures would be assembled atom by atom and molecule by molecule, from the atomiclevel up, just as occurs in nature. However, assembly at this scale has its own challenges. In school, children learn about some of these challenges when they study the random Brownian motion seen in particles suspended in liquids such as water. Theparticles themselves are not moving. Rather, the water molecules that surround the particles...
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Technology.
loose soil in this region, known as the Fertile Crescent, was easily scratched for planting, and an abundance of trees was available for firewood. By 5000 BC, farming communities were established in areas known today as Syria, Turkey, Lebanon, Israel, Jordan, Greece, and the islands of Crete and Cyprus. Agricultural societies in these places constructed stone buildings, used the sickle to harvest grain, developed a primitive plowstick, and advanced their skills inmetalworking. Trade in flint al...
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Memory (psychology).
memory span —how many items people can correctly recall in order. Researchers would show people increasingly long sequences of digits or letters and then ask them to recall as many of the items as they could. In 1956 American psychologist George Miller reviewed many experiments on memory span and concluded that peoplecould hold an average of seven items in short-term memory. He referred to this limit as “the magical number seven, plus or minus two” because the results of thestudies were so consi...
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Installer un µcontroller F210A
Zavio F210A Quick Installation Guide Please follow the installation steps below to set up your F210A IP Camera. Check the package contents against the list below. See P.1 Physical overview. See P.1 Install the hardware and connect all cables. See P.2 Microsoft OS: Use the software CD to install Intelligent IP Installer. See P.2 Access the IP Camera using Intelligent IP Installer. See P.2 Mac OS using Safari Browser. See P.4 Change light environment setting. See P.5 Change the Web I...
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Physiology.
III RECENT ADVANCES Among the most important advances of the 20th century are the discovery of new hormones; recognition of the role of vitamins; discovery of blood types; developmentof the electrocardiograph and electroencephalograph, to record the activity of the heart and brain; discovery of the cause and cure of pernicious anemia by GeorgeRichards Minot, William Parry Murphy, and George Hoyt Whipple, all American physicians; and greater understanding of metabolism, the role of enzymes, and...
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Isotope - chemistry.
depends on the fact that when water undergoes electrolysis, the lighter hydrogen isotope tends to come off first, leaving behind a residue of water that is enriched inthe heavier isotope. D Gaseous Diffusion This and the electromagnetic method of separating isotopes of uranium afforded the first large-scale separation ever achieved. The problem of separating uranium-235from uranium-238 arose in 1940 after the demonstration of the susceptibility of the 235 isotope to fission by neutrons. Uranium...
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Endocrine System.
thermostat. When the heat in a house falls, the thermostat responds by switching the furnace on, and when the temperature is too warm, the thermostat switches thefurnace off. Usually, the change that a hormone produces also serves to regulate that hormone's secretion. For example, parathyroid hormone causes the body toincrease the level of calcium in the blood. As calcium levels rise, the secretion of parathyroid hormone then decreases. This feedback mechanism allows for tight controlover hormon...
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Puzzle.
Visual puzzles involve searching a picture to find hidden or disguised figures or answering a question about some part of a visual illusion. For instance, the popular 19th- century prints of American lithographic company Currier & Ives featured hidden people, animals, and other objects. A 16th-century painting from Bukhara, Uzbekistan,of a camel includes hidden figures of 17 people, 10 rabbits, a monkey, and a dragon (Metropolitan Museum of Art, New York City). B Mathematical Puzzles and Logic...
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Aristotle
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INTRODUCTION
Aristotle (384-322
BC),
Greek philosopher and scientist, who shares with Plato and Socrates the distinction of being the most famous of ancient philosophers.
succession of individuals. These processes are therefore intermediate between the changeless circles of the heavens and the simple linear movements of the terrestrialelements. The species form a scale from simple (worms and flies at the bottom) to complex (human beings at the top), but evolution is not possible. C Aristotelian Psychology For Aristotle, psychology was a study of the soul. Insisting that form (the essence, or unchanging characteristic element in an object) and matter (the commonu...
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Aristotle.
succession of individuals. These processes are therefore intermediate between the changeless circles of the heavens and the simple linear movements of the terrestrialelements. The species form a scale from simple (worms and flies at the bottom) to complex (human beings at the top), but evolution is not possible. C Aristotelian Psychology For Aristotle, psychology was a study of the soul. Insisting that form (the essence, or unchanging characteristic element in an object) and matter (the commonu...
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Igneous Rock.
As a magma cools, the first crystals to form will be of minerals that become solid at relatively high temperatures (usually olivine and a type of feldspar known asanorthite). The composition of these early-formed mineral crystals will be different from the initial composition of the magma. Consequently, as these growing crystalstake certain elements out of the magma in certain proportions, the composition of the remaining liquid changes. This process is known as magmatic differentiation.Sometime...
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Coronary Heart Disease.
when a patient is at rest may indicate that the blood supply of the heart is not normal, and the ECG can often detect damage from a previous heart attack. In anexercise stress test, an ECG is recorded while a patient is performing physical activity such as walking on a treadmill or riding a stationary bicycle. As the intensity ofexercise increases, the doctor looks for specific changes in the ECG that indicate the heart is not getting enough oxygen. In cardiac catheterization, a long, thin, flex...
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Poliomyelitis.
Physical therapy helps patients with paralytic polio stretch and move affected muscles. This movement minimizes the atrophy, or shrinkage, of affected muscles andlimbs and builds strength. Exercises can also retrain working muscles to compensate for other muscles that have permanently lost the ability to move. Rehabilitativetherapy trains patients to use braces, crutches, and other devices that provide support and aid mobility. V PREVENTION OF POLIO Immunization with polio vaccine is the best w...
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Circulatory System.
C Additional Functions In addition to oxygen, the circulatory system also transports nutrients derived from digested food to the body. These nutrients enter the bloodstream by passingthrough the walls of the intestine. The nutrients are absorbed through a network of capillaries and veins that drain the intestines, called the hepatic portal circulation.The hepatic portal circulation carries the nutrients to the liver for further metabolic processing. The liver stores a variety of substances, suc...
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Comte, Isidore-Auguste-Marie-François-Xavier
1 Life Auguste Comte was born in Montpellier, France. He attended the École Polytechnique, from which he was expelled in 1816, for political reasons. Comte's main concern throughout his life was resolving the political, social and moral problems caused by the French Revolution. To that end, he embarked upon an encyclopedic work, which he first conceived under the inspiration of Henri de Saint-Simon , for whom he worked as secretary from 1817 to 1824. At that time, he proposed several pla...
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Welfare.
industrializing societies. Governments typically financed social insurance programs with tax funds and direct levies on the wages of potential recipients. Social insurancereplaced part of incomes lost when workers became disabled, were laid off, or had reached an age that forced them out of the labor market. Later, governments of Germany, France, Belgium, Sweden, and other countries developed forms of social insurance that provided population-wide, or universal,coverage. Such forms included chil...